Extracellular Vesicles of COVID-19 Patients Reflect Inflammation, Thrombogenicity, and Disease Severity.

Severe COVID-19 infections present with cytokine storms, hypercoagulation, and acute respiratory distress syndrome, with extracellular vesicles (EVs) being involved in coagulation and inflammation. This study aimed to determine whether coagulation profiles and EVs reflect COVID-19 disease severity. Thirty-six patients with symptomatic COVID-19 infection with mild/moderate/severe disease (12 in each group) were analyzed. Sixteen healthy individuals served as controls. Coagulation profiles and EV characteristics were tested by nanoparticle tracking analysis (NTA), flow cytometry, and Western blot. While coagulation factors VII, V, VIII, and vWF were comparable, significant differences were found in patients' D-Dimer/fibrinogen/free protein S levels compared to controls. Severe patients' EVs displayed higher percentages of small EVs (<150 nm) with increased expression of exosome marker CD63. Severe patients' EVs displayed high levels of platelet markers (CD41) and coagulation factors (tissue factor activity, endothelial protein C receptor). EVs of patients with moderate/severe disease expressed significantly higher levels of immune cell markers (CD4/CD8/CD14) and contained higher levels of IL-6. We demonstrated that EVs, but not the coagulation profile, may serve as biomarkers for COVID-19 severity. EVs demonstrated elevated levels of immune- and vascular-related markers in patients with moderate/severe disease, and may play a role in disease pathogenesis.

Low Risk of Neoplasia and Intraprocedural Adverse Events in Gastric Hyperplastic Polypectomy.

GOALS: Assess neoplasia and polypectomy-related adverse event (AE) rates in gastric hyperplastic polyps (GHPs). BACKGROUND: GHPs carry a risk of neoplastic transformation. The rate of neoplastic transformation and the risk of polypectomy-related bleeding are unclear in the West, as data are derived from Asian or small studies. The authors aimed to determine the rate of dysplasia and intraprocedural AEs in GHP polypectomies in a western cohort. STUDY: A retrospective study of 591 GHPs >1 cm resected in 491 patients in a single referral center on the occurrence of neoplasia and intraprocedural AEs. RESULTS: The mean age was 74.9±11.1 years, 57% female individuals. The mean polyp size was 2±0.8 cm. There were 11 neoplastic polyps (1.9%) with low-grade dysplasia, high-grade dysplasia, and cancer in 7 (1.3%), 2 (0.3%), and 2 (0.3%), respectively. Neoplasia was associated with age [9 (3.2%) for more than 75 years vs. 2 (0.7%) for less than 75 years; P=0.035], but not with polyp size or gender. Fifty patients (8.5%) had intraprocedural bleeding (IPB) requiring endoscopic intervention, with 3 hospitalizations. There were no perforations or procedure-related deaths. IPB was associated with polyp size and neoplasia. The adjusted odds ratio (95% confidence interval) for IPB was 1.63 (1.2-2.2) for a 1 cm increase in polyp size, and 7.4 (1.9-29.6) for the presence of neoplasia. CONCLUSIONS: The neoplasia rate in GHPs was 1.9%, lower than most previous reports, with no major intraprocedural AEs. Physicians may consider biopsy and follow-up in frail elderly patients, but the safety of this strategy needs further confirmation.